Jaw actuating means for tools



Dec. 18, 1951 A. R. RALSTQN 2,579,272

' JAW ACTUATING MEANS FOR TOOLS Filed Nov. 8, 1950 INVENT OR Arm 0M5. F/usra/v fl/S ATTORNEY fiatented bee. 18, .1951

UNITED STATES PA;

M inventionrelate's to a j aw actuating me mmetal shears; pliers, a'i' dthe like, aadh'a one of its objects the production ofa simple and efiicientmeans for ac'tuatihg'the jaws ofa tool in a to apply maximu press reiupon the jaws and to'facilita'te' quick and efficient ieleaseofthe' jaws g Y A 'furth'er' objct'of this invention isth, production of a simple and eff cient eccentrical ly mounted actuating'disc which is carried by'one handle and is bodily moved in one direction and is also rotated by mea s of movement of "the other'handle when the'liandles' are tassel-1km open the jaws of the tool, the closing'of the handles reversing this movement to close the Jaws.

Other objects and advantages of the'pres ent invention" will appear throughout the following specification and claims.

Figure 1 is a side elevational view of a tool in the nature of a pair of metaY'sh'e'ars, showing theactu'ating mechanism applied thereto;

Figure 2 is aside elevational view of the reverse side of the blade or jawi portion of the tool shown in Figure 1, the bifurcated portion which connects the upper handle to the lower jaw being broken away to show the connection of the upper jaw with the operating eccentric linkage;

Figure 3 is a fragmentary vertical sectional View taken on 'line 3-3 of Figure 1;

Figure 4 is a fragmentary longitudinal sectional view taken on line 4-4 of Figure 1;

Figure 5 is an enlarged fragmentary side elevational view of the actuating eccentric and connecting link, the pivot bolt being shown in section;

Figure 6 is a side elevational view of a modified form showing the actuating link leverage means applied to a tool of a pliers type.

By referring to the drawing, it will be seen that In designates the lower jaw or blade of the tool which is provided near its rear end with an upstanding bifurcated portion ll defining a socket l2. An upper jaw or blade I3 is pivotally secured within the lower end of the socket l2 by means of a suitable ivot bolt or pin [4. In the form shown in Figures 1 and 2 the upper jaw I3 is provided with a cutting edge l5 and the lower jaw is provided with a cutting or shearing edge I6.

An actuating handle I! is pivotally secured to the rear end of the lower jaw ID by means of a pivot bolt or pin IS. A companion actuating handle i9 is pivoted within the upper end' of the 2 bifurcated portion 1 I of, the'jaw Ill byine'anso a"pivot"bolt"or'pin 0' "In a 4, th a'ipai r i 'of spac f w rdl a ipw rf 1y protruding" circularfextensfions"2|. A discf22i15 eccentrifcally pi etwe'enthe extensions? 21 upon ajourna'l ol or"pin 23;thereby-defi-ni'rig an a tu ne'jec e Q- Afpairof'ja ""ac connedted att i h bpe 'p'in 25;and-theemanagement journalledin matching' or transvrs'ely'ali'gne apertures zli in he'reaifportions ot-the links 24. Thee'ccentric "--22 5a1"i-i e-a int gral-arm '2Twl iichfis'p ot 1y cpj ne'cted-at*its'rear fend to thepo'r' 10 b shown in dotted lines in Figure 1. The upward swing of the handle H! at the same time will swing the arm 21 upwardly thereby rotating the eccentric disc 22 to pull the links 24 rearwardly and to thereby open the upper jaw relative to the lower jaw of the tool. By means of this structure, a double or two-fold movement is obtained, first the rearward bodily movement of the pivot bolt 23 rearwardly, and second the rotary movement of the eccentric disc 22. A maximum rearward pull upon the links 24 to swing the jaw I3 is obtained within a minimum amount of space and a positive and forcible leverage action is thereby produced.

As is shown in Figure 6, the same leverage may be employed in connection with a pair of pliers, as that shown in Figures 1 and 2, wherein a pair of shears is shown. In Figure 6, the numeral 3| designates one jaw of a pair of pliers, and a companion jaw 32 is pivotally connected thereto by a pivot bolt 33. The jaw 32 is pivotally connected at its rear end at 34 to a link means 35, which is in turn engaged by means of an eccentric disc 36 similar to the disc 22 referred to in Figures 1 and 2. One handle 31 is pivotally connected by a pivot bolt or pin 38 to the top of the jaw 3|, and a companion handle 39 is pivotally connected to the bottom of the jaw 3|, by a pivot bolt 40. The handle 39 is in turn pivotally connected to the disc 36 by means of an eccentrically mounted journal bolt or pin 4| similar to the bolt 23 shown in Figures 1 and 2. An arm 42 is formed integral with the disc 36 and is pivotally connected to the handle 31 by means of a pivot pin 43. The operation of the above described leverage is the same as that described with respect to Figures 1 and 2.

It should be understood that the leverage herein described maybe employed in any tool of the general type illustrated within the spirit of the invention, whether the tool be a pair of shears or pliers, and it should be further under: stood that certain detail changes in the mechanical structure and arrangement of parts may be employed without departing from the spirit of the invention, so long as such changes fall within the scope of the appended claims.

Having described the invention, claimed as new is:

,1. A tool comprising a primary jaw and a companion jaw, means pivotally connecting the jaws, a handle pivotally connected to the primary jaw and a companion handle also connected to the primary jaw in spaced relation to the pivot connection of the first mentioned handle, a link connection connecting the companion jaw with the first mentioned handle, said link connection including an eccentric member pivotally secured to the first mentioned handle, and a rigid arm carried by said eccentric member and pivotally connected to said companion handle to move the jaws toward and away from each other as the handles are opened and closed.

2. A tool comprising a primary jaw and a companion jaw, means pivotally connecting the jaw a handle pivotally connected to the primary jaw and a companion handle also connected to the primary jaw in spaced relation to the pivot connection of the first mentioned handle, a link connection connecting the companion jaw with the first mentioned handle, said link connection including an eccentric disc pivotally secured to the first mentioned handle in inwardly spaced relation with respect to the pivot connection of the first mentioned handle and the primary jaw,

what is 4 and a rigid arm carried by said eccentric disc and pivotally connected to said companion handle to move the jaws toward and away from each other as the handles are opened and closed.

3. A tool comprising a primary jaw and a companion jaw, means pivotaly connecting the jaws, a handle pivotally connected to the primary jaw and a companion handle also connected to the primary jaw in spaced relation to the pivot connection of the first mentioned handle, a link connection connecting the companion jaw with the first mentioned handle, said link connection including an eccentric disc pivotally secured to the first mentioned handle in inwardly spaced relation with respect to the pivot connection of the first mentioned handle and the primary jaw, a rigid arm carried by said eccentric disc and pivotally connected to said companion handle to move the jaws toward and away from each other 'as the handles are opened and closed, and the eccentric disc being bodily movable toward the handles and also being rotatable toward the handles as the handles are opened to provide a two-fold leverage action to open said jaws.

4. A tool comprising a primary jaw and a companion jaw, means pivotally connecting the jaws, a handle pivotally connected to the primary jaw and a companion handle also connected to the primary jaw in spaced relation to the pivot connection of the first mentioned handle, a link connection connecting the companion jaw with the first mentioned handle, said link connection including an eccentric member pivotally secured to the first mentioned handle, a rigid arm carried by said eccentric member and pivotally connected to said companion handle to move the jaws toward and away from each other as the handles are opened and closed, and a longitudinally adjustable stop wedge carried by one handle and engageable by the companion handle to adjustably limit the closing of the handles relative to each other.

ARTHUR R. RALSTON.

No references cited. 

